The main factor that can affect your playing when moving from a piano to a keyboard is whether or not your keyboard has weighted key action, or is merely "touch sensitive". This, coupled with the fact that keyboards have volume controls (sometimes more than one) on not just themselves, but also on the sound system they're connected to, can make performing with dynamics tricky. On a piano, you can gauge how your dynamics are balancing with other performers, but on a keyboard this is a little more difficult because of the fact that you may not always directly hear what you play at the volume the audience or other members of your band will. Similarly, you'll find that levels might be different at different venues, so you cannot count on consistent playing to actually produce consistent results. Also be aware that different voices/instruments on the keyboards may vary greatly in how they respond to dynamics.
Something I still personally have to watch is damper pedal usage. I really don't like playing entirely without a pedal, because it makes me feel like my playing is sometimes too choppy. However, using a pedal with a keyboard, be especially aware of how it affects the various instruments/voices differently. Strings, for instance, generally don't naturally decay in volume like pianos do, and so one can wind up with a mushy mess if pedaling just like piano. However, to give a proper effect for some instruments, abrupt playing by trying to avoid the pedal may not sound right either.
Related to this, certain bass elements may get lost more easily on instruments like string or organ than on piano. Either moving down an octave with your left hand or opting for a walking or moving bass line rather than staying on repeated notes can help with this.
My main advice would be to suggest rehearsing in your performance venues when possible and recording yourself doing a few different things from a distance while rehearsing with your group so you can gauge how you're sounding as part of the ensemble to the audience. Monitors and headphones don't always give the most accurate impression.